Ship&#39;s propeller.



No. 867,148. PATENTED'SEPT.24,190'7. I

' P. PIERI. I

SHIPS PROPELLER.

APPLICATION FILED 001215. 1906.

UNITED POMPEO PIERI, OF PARIS, FRANCE.

SHIPS PROPELLER.

Specification of Letters Patent.

Patented Sept. 24, 1907.

Application filed October 15, 1906. Serial No. 339,058-

To all whom "it may concern:

Be it knownthat I, POMPEO PIERI, a citizen of the Kingdom of Italy,residing at 70 Avenue dIena, Paris, in the Republic of France, haveinvented new and useful Improvements in Ships Propellers, of which thefollowing is a specification. I

The present invention relates to propellers for ships and particularlythat kind in which they are arranged on the longitudinal axis of theship and inside the hull,

instead of being arranged on the sides or at the stem as in the case ofships with ordinary wheels or screws.

The invention is intended to procure greater speed for the expenditureof a given amount of motive power by using the action of the propellerdevices on the water in amore efIicient and complete manner.

The invention consists for this purpose of a special arrangement of thewheel or propeller device with composite paddle boards, which arecombined in such a way as to utilize the action of the propellers on thewater in as complete a manner as possible.

In the accompanying drawing: Figure 1 .is an elevational view of therear portion of a vessel provided with my improvement, parts of thevessel being broken away. Fig. 2 is a transverse section. Fig. 3 is aperspective view of one of the propellers one of the paddle boards beingbroken away.

The hull of the vessel is divided longitudinally from the stern up to acertain distance from the bow into two parts so that along the greaterpart of the length of the vessel the same has two parallel hulls a, awhich are connected together at a certain distance from the bow so as toform one body and are likewise connected together at the rear at acertain height above the waterline by a sort of bridge or tunnel at (1These two hulls thus leave a kind of channel I) between them withinwhich the propellers c are lodged. The propellers may vary in numberaccording to the dimensions of the ship and the power of its machinery.

Each of the propellers constructed according to the present invention(Fig. 3) consists of a hubd. on which branches e are radially arrangedwhich may be three in number as shown in the example given but may ifnecessary be more numerous. They are arranged on the hub d symmetricallyand with regular spaces. Each of these branches or paddles instead ofbeing simple is itself formed of several composite blades, viz: of acentral blade 8 having a V-shaped transverse section and secured on bothsides to several lateral composite paddles (e e e 0 Fig. 3) which areformed and arranged in such a manner as to act on the water displaced bythe central blade e so as .to increase the efficiency of the action ofthe propeller paddle or propeller arm on the water. The cutting edge orpoint a; of the paddle or central V-shaped arm e, 'i. e. the edge withwhich this paddle attacks the water, when the wheel or propeller isrotating in the direction of the arrows,

is arranged to be practically radial with regard to the hub d, whereasbehind this cutting edge, the blades of the arm 8 are bent round so asto form concave surfaces which'meet the lateral bent blades 6 a forminglikewise with said blades of arm 6 paddles having a transvesse V-shapedsection. The cutting edges y of these latter blades likewise attack thewater behind the cutting edge or of the central blade e. Moreover, thebent lateral blades 6 c are joined to the bent blades e 0, with whichthey also form blades having a V-shaped transverse section. bladesattack the water behind the cutting edge y and so forth. In this mannerthe water thrown off to the sides by the central blade 6 is received bythe lateral blades e e which take up this water and act upon the same,whereupon the water thrown off bythese lateral wings or blades is againtaken up by the lateral blades 6 c which act in turn on the water, sothat the useful effect is increased to a very considerable extent.

In order to further increase the useful effect of the propeller on thewater, each of the'wings or blades of the central arm a as well of thelateral blades 0 e e, e is itself composed ofa certain number ofelementary blades f, g, h (Fig. 3) which have a bent section in a radialdirection of the arm of the propeller. Each elementary blade resemblesthe shape of a spoon the concave side of which is turned in thedirection of the movement of the propeller-arm when the latter revolves.In consequence of this arrangement the water which escapes radially frombeneath the first of the spoons or elementary blades f of each of thewings or composite blades 0, e e a e is taken up by the second spoon gof the same composite blade and so forth, so that the useful effectobtained is increased further.

What I do claim as my invention, and desire to secure by Letters Patent,is:

1. In shipshaving their propellers arranged on their longitudinal axisand inside the hull, a propeller having a hub provided with branches orarms arranged radially and symmetrically, each arm consisting of acentral blade formed of two wings bent in a transverse direction andcoming together along a ridge which is practically radial with regard tothe hub so as to present a V-shaped transverse section the point or edgeof which attacks the water, said central blade being provided on eachside with one or several simple lateral blades which are bent in atransverse sense and form each with the corresponding wing of thecentral blade, or with the simple adjacent blade, likewise a doubleblade with a V-shaped transverse section, whereby the edge of saiddouble blade is thus made to attack the water behind the edge of thecentral blade, each of the wings of the central blade as well as of thelateral blades being itself formed, in a longitudinal or radialdirection of the branch of the propeller, of several pallets or elementsjoined together and resembling the shape of spoons, the concave side ofwhich is turned downward in the direction of the movement of thepropeller, each of the pallets or element an active surface having aV-shaped section in a radial direction, substantially as described.

The cutting edges 2 of the latter elements forming likewise with theadjacent pallet or 2. In a propeller, the combination of a hub, a seriesof ridge, and said central portion as well as said lateral 10 radialarms or blades, each consisting of a central portion blades being eachformed of a plurality of elements joined formed of two wings extendingin a direction transverse together, spoon shaped, and extending radiallyout from to the shafl and meeting at an angle to form a ridge and thehub, substantially as describedv thereby present a V-shaped transversesection, the edge of 1 which attacks the water, said central portionbeing pro IOMI k0 vided on each side with lateral blades which likewisemeet Witnesses at an angle to form ridges V-shaped in cross section,which LOUIS RINUY,

latter ridges attack the water behind the first-mentioned lI. DE SOTO.

